1. Field of the Invention
Embodiments of the present invention relate to computer guided cryosurgery and more particularly to a system for assisting an operator in placing and operating at least one cryosurgical probe in a region of interest in a human patient.
2. Description of the Related Art
Cryosurgery involving the use of cryosurgical probe assemblies typically involves the use of cryoprobes that are each attached to a handle that are, in turn, connected to a high-pressure fluid line attached to a fluid source. Cryosurgical ablation of the prostate has generally required relatively small iceballs, i.e. 4 cm diameter by 6 cm length. For other applications, for example, renal applications, relatively larger iceballs are desired. Many other potential applications of cryosurgery may also require larger iceballs such as to ablate renal tumors, hepatic tumors, and pulmonary and thoracic tumors. Relatively large iceballs may also be required for palliative intervention.
The ultimate goal in a cryosurgical procedure is to freeze all tumor tissue by lethal ice to kill the tumor and not to freeze any benign tissue surrounding the tumor tissue by lethal ice to avoid complications. Due to variations of tumor size and shape, it has always been a great challenge for a cryosurgeon to precisely place multiple cryosurgical probes into desired locations of a tumor and control them so as to generate an optimum lethal iceball that is tailored to fit the tumor.